Hacker News new | ask | show | jobs
by natch 1347 days ago
Profanity alert. Don’t read this if you are sensitive.

You. Do. Fucking. Not. Need. An EV charger, to charge your EV. A 110 or 220 outlet with a cord and an adapter will work just fine. Apologies for the US centric terminology but I expect the situation is roughly the same (though numbers vary) elsewhere.

We did TWO Teslas in an apartment for two years sharing (alternating cars) a single plug of a single 110 outlet. It was fine. Yes, on days where you do big trips, there’s a supercharger visit, But normally, an outlet is totally sufficient.

An installed charger does add some very, very minor convenience (no adapter, big deal… not worth the cost). And if it needs to be shared and bills split, that’s different. But for basic charging no special installation is needed as long as you can reach.

5 comments

I know a person who has done this with their tesla for like 6 years and to the point that they will not plug their tesla into anything more powerful because they think that charging it at 2kW is keeping their battery pristine. I don't think they realize that by pressing that accelerator pedal they can load the battery with ~300kW and therefore 2kW or 11kW or 22kW charging makes no effing difference.

Their daily commute is less than 100km so they have no problems charging the batts with their granny charger.

In our household we have one to four ~90% capacity commutes per week and being able to always get a full charge with the 11kW charger helps a lot.

So YMMV. I agree with you. Especially agree with the point that people should analyze their usage, maybe get some experience living with an EV and never give up on the first mental hurdle without even trying.

If you buy electricity at the (hourly) market rate, you want to charge when it is cheapest and charge reasonably fast. On a typical 11kW home charger here in EU, that means about 6 hours for full charge or 1..2 hours for daily top-up. All the benefits for buying the electricity at hourly demand based rate disappear when full charging times approach 24h.

This has two benefits: it is cheaper to charge and the grid works more efficiently — price is lower when the demand is low and/or production is high.

> when full charging times approach 24h.

200 miles a day is not the median driving pattern. It's closer to 30 miles

In our area the higher price (peak demand time) was during a window about 6 hours long. So we were able to charge a maximum of 18 hours a day while avoiding that window. Now we have 220 which makes things easier, but still no need for a charger installation.
An installed charger is not needed for scheduled charging if the car already does it. Buy an EV with good modern features and you’ll be fine with just an outlet.
To be cost efficient with day-ahead hourly pricing, you need a faster (level 2) charger as there are only few extra-cheap hours in a day.
How long before you recoup the cost of the charger though?
There is absolutely no financial advantage to having an installed charger versus an outlet. There are other advantages. It might fit your hand better during the 2 seconds it takes to plug in. It might be better in the rain if your outlet is exposed to driving rain in wind. It might look more impressive to the neighbors. It looks more impressive to the landlord or wife or anyone who might be approving a budget for upgrading wires inside a wall or upgrading a panel. It does not save any money.

If you are thinking of charge scheduling, the car does that. Or should… if you buy an EV from a good EV company, not an old crusty legacy automaker.

The point with scheduling is that on a normal plug, it make take long enough to charge your car that you can't charge it completely during the time window where electricity is the cheapest. So the parent comment was arguing you need faster charging to save money by doing all your charging in that time window.

But yeah I have a hard time believing it's gonna be a big enough saving to offset the cost of the charger.

Cars have the scheduling built in.

Unless you buy an electric car from one of the companies that is actively promoting gas cars and trying to make their own electric cars super crappy in hopes the entire concept will fail. Meaning, any gas car maker.

Yes, scheduling saves money. But even paying high electric rates during peak hours can still be way cheaper than gas, depending on what exact rates we're talking about, which varies by location.

But the plug has nothing to do with scheduling if you just use the car's own scheduling or plug/unplug yourself.

Being able to charge with 11kW (level 2 charger) instead of 3.5kW (level 1 charger) allows to charge daily 20kW within 2 hours instead of 6.

Two days ago kWh was at 0.03€ For two hours only, after 0.41€ peaks during the day. Of course this scheduling is automatic. Using Gridio (https://www.gridio.io/) for that.

Payback time here is about 100 full charges (IONIQ5, Nordpool day-ahead pricing).
We bought a second hand EV with ~60 miles range, and a standard 240V (UK) outlet wasn't enough for us. We got a charger installed. It turned out that around city the range was fine, but if we wanted to do [multiple] outings in a day, we couldn't. Getting a 7kW charger made all the difference, because it can recharge the car in a couple of hours in the middle of the day.

So my caveat to your claim would be: only if your EV itself has enough range, which means you're limited to newer EVs, rather than buying older ones on the second hand market that were manufactured with less range (and by now probably only have ~80% of their original, lesser range, remaining).

This is a bad idea because the risk of fire is very high. The electrical wires aren't built for the high load of charging a car, and doubly so if they happen to be old. That's why electricians should always draw completely new wires, to make sure that everything is fresh and able to handle the load.

That it's been working for you for a few years does not invalidate this point, in the same way as not wearing a seat belt is unsafe.

Yes always use higher spec outlets made for heavy duty appliances, such as kitchen outlets. And yes it's a good idea to get your setup checked, and upgraded or repaired if necessary.
That only works if you have a short commute. I've charged my Tesla 3 maybe 3 times on 110 and it's a dumpster fire. One time parked at an AirBnB hoping to gather enough juice over the course of a weekend to get useful range heading home while we carpooled with friends.

3 miles per hour of charging is simply not enough. 12h x 3mph = 36mi range added, and that's not enough to reliably expect even a 30 mile roundtrip, let alone any errands you might run. I'd say we go through easily 55-60 miles of range for a 42mi commute. Plus, you're charging at peak hours for part of that.

Obviously I'm not saying you're lying, you did it, that's great, but you sure weren't driving many miles in both cars.

As I said we augmented with supercharging as needed. Doesn’t work for everyone though as not everyone lives near a supercharger. And there was one person working from home, and one with a short commute.